Controlling apparatus for highway crossing signals



Dec. 30, 1941.` c. w. .FNLOR CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNAL 2 Sheets-Sheet l Filed July 28, 1939 SWW@ HIS A'rToRNEY Si En %W m swg m Dec. 3o, 1941. QW, FMLR n 2,268,193'

CONTROLLING APPARATUS FOR HIGHWAY CROSSING sIc-NALS Filed July 28, 1939 2 sheets-sheet 2 INVENTOR Cbczplef Faz'lon A BY.

` HIS ATTORNEY Patented Dec. 30, 1941 UNITED STATES-*PATENT OFFICE CONTROLLING APPARATUS FOR HIGHWAY CROSSING SIGNALS Charles W. Failor, `'Forest Hills, Pa., assignor to The Union Switch & "Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application .my ze, 1939, serial No. asigne 7 Claims.` (Cl. 246-130) l My invention relates to controlling apparatus l One feature of my invention is the provisionof means for preventing the displaying of la `false indication by the highway crossing signals. when the main source of power fails.. Another feature of `my invention is the provision of lmeans for keeping a` storage battery in properly charged condition when the storage battery is useclas the auxiliary source of power.

I shall describe several forms of apparatusembodying my invention, and shazl then point out the novel features thereof in claims.

In the accompanying drawings, Fig. l is a diagrammatic View illustrating one form of apparatus embodying my invention as applied tohigh- Way crossing signals of the aShinglight type. Fig. 2 is a diagrammatic view showing modifications of portions of the signal control and operating circuits shown in Fig. 1. Figs. V3, `i and 5.

`are diagrammatic views `showing modifications of the control of the charging apparatus for an auxiliary source oi powerA comprising a storage battery shown in Figs. 1 and 2.` i

In each of the views,` the contacts operated by the `various relays or other devices are identiiied by numbers, such numbers having `,distinguishing prefixes from which they are separated by a dash when the contacts are shown apart from the relay or other device bywwhich they are operated; The prefix for each of these contact numbers comprises the reference character for the respective relay or other device. Forexample, contact STR-31, shown .in the control circuit for relay 5TRP, is identiiied by the number 3l separated by a dash from `the prefix ETR which is the reference character for relay 5TH by which this contact is operated.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1,the reference characters 4 and da designate the track rails of a stretch of `railwaytrack intersected by a highway H. Insulated joints 2 divide these track rails vinto three sections including sections a-b and` c--d which extend in oppositeidirections from the Iintersection of the highway. H with `the railway` track, and including a short section b--c at the intersection.

Impedance bonds n of a usual and well-known type are provided for transmitting train propulsion current past the insuated joints. The train propulsion current can be alternating currentoi any suitable frequency, or can be direct current.`

A signal of `the ashing light type comprising two. units RSA and RSB is located adjacent the intersection for governing traiic movements .in`

one direction on the highway H across the intersection, and a second signal of the same type comprising two units LSA and LSB is located adjacent the intersection for governing traiiic movements in the opposite direction on highway H across the intersection.

Each track section is `provided with a traic responsive circuit, such for example as a track;`

circuit in which current is supplied to one end of track section a-b, h c or c-d through the usual resistor 6 by secondary windings IT, 3T and 5T, respectively, of a track transformer TT. Resonant units IRU, SRU and ERU are connected across the rails Vadjacent the opposite ends oi track. sections a-h, b-c and c-d', respectively. Each of these resonant units comprises a transformer l, a condenser unit 8 anda transformer 9. The purpose of the resonant units `is to permit current ofonly the frequency supplied by transformer `TT to passto the full wave rectiers lil for energizing direct current track relays ITR, STR and STR for sections a-b, b-c and c--d, respectively. In addition, if one of the condenser units 8 should become short-circuited, an unbalanced condition of the train propulsion current. could notcause the associated track relay TR to become falsely energized.

Track transformer TT `is normally energized by current from a main source of power having terminals BX and CX connected with terminals ll and l2, respectively, of primaryswinding P. Other transformers designated by the reference characters TA, TB, TC and TD are also normally energized by current from the main source supplied to their primary windings l5, 18, Ziifand1 21, respectively.

yPower-off.relays .POA-.and POB are normally energized by current from secondary'windings I6 and I9 of `transformers TA and TB, respectively, and henceztheserelays become deenergized when themain source of power fails. When relay PGB becomes deenergized, primary Winding P of` track transformerTT is energized yfrom. an-a-uxiliary source of power comprising astoragebattery 2Q, througha tuned alternator' TUA.

Tuned alternator TUA comprises a movable` contact element 22, a control winding 23 fixed contact elements 24 and 25, and a control contact element 26. Movable contact elem-ent 22, in the normal or deenergized position in which it is shown in the drawings, connects with the control contact element 25.

Upon the deenergization of relay POB, a control circuit for tuned alternator TUA becomes closed, passing from terminal BB of battery 2Q, through contact 22-25 of tuned alternator TUA,

control winding 23, and the back point of contact 42 of relay POB to terminal CC of battery 2Q. This causes contact element 22 to move to the right as shown in the drawings, where it engages fixed Contact element 24E and dis'engages control `Contact element 2, thereby deenergizing control winding 23.

terminal Il, and when contact element 22 en gages contact element 25, current from battery 2Q passes from terminal I4 of primary winding P through a portion of primary winding P in the opposite direction to terminal II, causing alternating current to be induced in the secondary or track windings IT, 3T and 5T of transformer TT.

When transformer TT is thus energized .fromv battery 2Q through contacts 22--24 and Z2-25 of tuned alternator TUA, transformer TD is energized from terminals II and I2 of primary winding P which then acts as an autotransformer. A checking relay CH is energized from secondary winding 28 of transformer TD through a rectifier 29.

Directional control means comprising a relay of the well-known interlocking type, having windings IXR and 5XR, is controlled by checking relay CI-I and 'by track relays ITR, 3TR and 5TR.

A flasher relay FL is controlled by back icontacts associated with windings IXR and 5KB, of the interlocking relay. `As shown in the drawings, relay FL is equipped with twov movable contact elements 56 and 59 which, when relay FL is energized, swing. back and forth between lefthand and right-hand positions. In the left-hand position, contact element 56 engages a fixed contact element 51, and in the right-hand position, contact element 56 engages a fixed contact element 58. Similarly, in the left-hand position, contact element 59 engages a fixed contact element Eil), and in the right-hand position engagesV a fixed contact element 6I.

When a train approaches the intersection, the signal lights RSAL, RSBL, LSAL and LSBL of signal units RSA, RSB, LSA and LSB, respectively, are lighted by circuits energized from the main source of power and including a back contact of winding I XR or 5XR and the contacts of flasher relay FL. The operation of the contact elements 56 and 59 of relay FL causes the signal lights to flash, so that the lights for each signal are `alternately lighted.

In the event of failureof the main source of power-off relay POB and by a contact of track charged from secondary winding I'I of trans-r former TA through a rectifier 3U.

A track relay repeater STRP is controlled through a front contact of relay 5TR, and is of a slow releasing type. V

A charging control relay CR is energized by current from battery 2Q in a circuit controlled by relay 5TR in multiple with a contact of track repeater relay STRP. The parts of the apparatus are so proportioned that relay CR, upon becom ing energized, will open its back contact 4I only when battery 2Q is, or becomes, fully charged.

The charging circuit for auxiliary sourcel battery.2Q is normally closed through a resistor 3| which is at times shunted by -back contact 4I of charging control relay CR. Charging current for battery 2Q is supplied from secondary winding 2l of transformer TC through a rectifier 32. A manually controllable switch SW is shown in the primary control circuit for transformer TB for at times opening this circuit by hand.

Referring now to Fig. 2, the circuits for controlling the checking relay CH, track transformer TT, and tuned alternator TUA for the modied form here shown are the same as in Fig. 1, and have therefore been omitted from Fig. 2.

In Fig. 2, the interlocking relay windings IXR and 5XR are controlled only by the track relays. The interlocking relay is here shown provided with the well-known type of contact referred to as a. agman contact, which is a front contact which opens if the associated Winding is rst deenergized, but which remains closed if the associated winding becomes deenergized after the other Winding for the interlocking relay has become deenergized. `Flagman contacts 61 and IKR-I2 are associated with winding IXR, and lagman contacts 66 and SKR-'I3 are associated with winding 5XR.

A slow releasing signal relay XRP is controlled by a contact of checking relay CH and by iiagman contacts of windings IXR and 5XR. Flasher relay FL is here controlled by a back contact of relay XRP. The signal lights are here controlled by a back contact of relay XRP instead of by back contacts of the interlocking relay. Poweroff relay PO-AA has a pick-up circuit including a 'front contact of relay XRP, and a stick circuit including one of its own front contacts. Charging control relay CR is here controlled by flagrnan contacts of the interlocking relay in multiple with i a back contact of relay XRP, which are in series with a front contact of relay POB.

Transformers TB and TC, battery IQ, and rectier 30 are omitted from the modied form of apparatus shown in Fig. 2. Power-olf relay POB is here controlled from secondary winding lI6 of transformer TA instead of from transformer TB shown in Fig. l. The contact 4I of relay CR, and resistor 3|, are here placed between rectifier 32 and secondary winding I'I of transformer TA instead of between rectifier 32 and battery 2Q as in Fig. 1. Switch` SW is here shown in the primary control circuit for transformer TA instead of in the primary control circuit for transformer TB shown in Fig. l.

In the modification shown in Fig. 3, repeater relay STRP is not used. A contact of track relay 5TR is here included in series with back contact 4I of relay CR. The apparatus shownrin Fig. 3 is otherwise the same as in Fig. 1.

`In. the modification shown in Fig. 4, the control circuit for charging control `relay .CR includes a contact Mwhichis periodically opened by a cam 33 operated by `a synchronous motor M. Contact 34 of motor M is used` instead of` the contacts of track relay STR and repeater relay STRP shown in Fig. l, Aand therefore relay STRP is eliminated from theA modication shown in Fig; 4.

InrFig. 5, charging control relay CR is controlled by pole l changingA contacts of` track relay STR instead of by the contacts of relays STR and STRP asshown `in iFig.` 1. `Relay STRP is therefore not-used in the modification Vshovln in1`E-ig.` 5. i

Having thus described, in- `general, the arrangement and operationnof the several forms of apparatus shown embodyingmy invention, I shall now` describe in detail the operation ofthe apparatus.

As shown in` the drawings, all parts are in the normal condition, that is, relays ITR; 3TR, STR, IXBf-SXR, POAfPOB, STRP, CR-and CH are energized; also relays POAA and XRP of Fig, 2

are energized; motor M1 of Fig. 4 is constantly operating cam 33; relay FL and tuned'v alternator TUA are deenergized;` switch SW is closed; and the lamps of the signals are unlighted.

In the form of apparatus shown in Fig, 1, relay POA is shown energized from secondary winding `I6 of transformer TA, and direct current relay POB is shown energized from secondary winding I9 of transformer TB, one half- Wave of the current `from secondary I9 passing through the left-hand portion of the winding of :f

relay lPOB and through an asymmetric unit 3S such, for example, as a half-wave copper oxide rectifier, and the `other half-Wave of the current from Winding I9 passing through the right-hand portion of the Winding of relay POB through asymmetric unit 36.

The storage battery IQ is here shown being charged from secondary Winding I 'l of'transformer TA through full-wave rectifier 30.

With track relay STR energized, track repeater relay STRP is energized by its circuit passing from terminal BB of` battery 2Q, through contact STR-31,` and the Winding of relay STRP to terminal CC of battery 2Q.

` Charging control relay CR is shown energized by its circuit passing from terminal BB of battery 2Q, through contact STRQBB, contact 40 ci relay POB, and the` winding of relay `CR to terminal CC of battery 2Q. The charging circuit for battery 2Q is shown closedthrough resistor i Biand includes rectier 32.

With the track relays energized and relay POB energized, the primary Winding21 of `transformer TD is energized by a circuit passing from l terminal BX of the main source of power, `through the iront point of contact.42 of relay POB, contacts STR-43, 3TR-44, and ITB-4S in series with each other and in multiple` with contact 426.. of relay CH and primary Winding -21 of trans- 'iormer TD to terminal CX ofthe main source of power. With primary Winding` 21 of transformer `TD energized, checking relay` CH is energized from secondary Winding 28 of transformer TD 'through rectifier 29. e

With relay POBi energized, `primary Winding P of track transformer TT is energized by a circuit passing from` terminal BX, through the front point of contact 42 of VrelayPOB, terminal it of` primary Winding` P, primaryzwindinglt'o the left ofterminalv il, .and terminal I2 of primary winding Pfto terminal CX.

Wit-h checking 'relay CH and the trackrelays energized, Winding IXR ofthe interlocking relay lli is energized` by a circuitV passing from terminal B of battery 1Q, through rcontact CH-41, contact 480i relay STR, contact 49 of relay lTR, and winding `IXR to terminal C of battery 1Q. Winding SXR isalso energized by a circuit passing from terminal B, through contact CH-41, contact 4Bv of relay 3IR, contact: S0 of relay STR, and Winding.` SKR tol terminal` C.

. `I shall assume that a train moves over the stretch oftrack from left to right as shown in rhe drawings, which I shall assume is the eastbound direction. When the trainenters section c b, relay ETR becomes deenergized, thereby releasing-contact 4.9 which opensthe circuit previously traced for, Winding IXR. Relay FL then becomes energized by a circuit passing from terminal` B,through contactnSl of Winding IXR, and winding of relay` FL to terminal C. Contact element Sii )of relay FL thereupon moves to one of` its` extreme` positions, which I shall'assume is to the left, Vin which it engages contact element 5i'. Lamp LSAL of signal unit LSA is now lighted by a circuit passing `from secondary windinglt ,of transformer TA, through the front point of contact 'S3A of relay POA, contact SS of f relay Winding` IXR, contact Sli-S1 of relay FL,

lamp LSAL, and the front point of contact 62 of `.relay POA back to secondary Winding I6 of transformer TA. At the same time, lamp RSBL of signal unit RSB is lighted by a similar circuit `which includes` contact 59-60 of `relay FL ingized, and also continues to` remain energized after contacts STR-44 and STR- '43 `become opened when relays STR and STR become deenergized.

` When the train enters section 13e-c, relay STR becomes deenergized, thereby deenergizing winding SKR.. On account of winding IXR being already deenergized, contact S2 of Windin'gSXR is kept from closing.

Relay STR, `upon becoming'deenergized, opens its contacts STR- 3l and STR-38m the circuits previously traced for relays STRP and CR, respectively. Relay CR is therefore deenergized, causing its contact` 4l to form a shunt path around resistor 3| inthe charging circuit for cattery 2Q. Relay STRP being of a slow releasing type, its contact 39 does not at once close,`

` until battery 2Q becomes fully charged.

When the train leaves Vsection b-c, Winding IXR' `again becomes energized by (its circuit previously traced. 'Contact Sl offwinding FIXR;

i the interlocking feature.

e apparatus embodying my invention is so designed and proportioned that normally in the event of failure of the main source of power, tuned valternator TUA will start operating, and through` its contacts, the auxiliary source of power, battery 2Q, will energize transformer TT vbefore vtrack relays ITR, 3TR, and 5TR have had time to release their front contacts, and hence the front contacts of these relays will re- `main closed. If, however, due to a loose connection or to some other cause, the tuned alternator TUA fails tostart immediately, causing the track relays `to. become deenergized and open their front contacts, checking relay CH will ensure safe control of the highway crossing signals by the interlocking relay. l l I. shall now assume that the main source of power. fails, and 'thatfor some reason the tuned alternator fails to start ,operating immediately, and thathence the track relays become deenergized.1 I shall further assume that track relay ETR opens its front contacts before relays ITR and STR. openV theirs. The interlocking relay armature associated with winding 5X5. will theres foredrop before the armature associated with winding IXR drops. .In the well-known interlocking. relay operation, the armature of winding 5XR will therefore close its back contacts 52 and 54, but the armature of winding IXR willbe prevented from closing its back contacts 5| `and 55. Relay FL then becomes energized by a circuit which is the same as the circuit previously traced except that it includes contact 52 of winding EXRinstead of contact 5| of winding IXR.` The signal lights will then be flashed as previously described.

I shall also further assume that before either the mainsource Aof power `is restored or the track circuits are energized from the auxiliary source, an yeastbound train enters section ca -bi, and' that the main source of power is then restored or the auxiliary source becomes operative to energizerelays 3TR and 5TR. On account of the failure of both the main and auxiliary sources of power, checking relay CH has become deenergized and its contact CH-41 has opened. Relay CH cannot again become energized while thetrain roccupies section d b, and hence thev winding 5XR cannot become energized,v although relays 3TR and STR are now energized.

. Winding 5XR will therefore remain deenergized,

and its back contacts 52 and 54 will remain closed, causing the lampsof the signals to be ashed while the train is approaching the crossing.

l I fmthe back contacts of winding SXR were opened while theback contacts of winding XR were still held open,` the signal lights would be extinguished before the approaching train reached theintersection, which would,of course, be a dangerous condition. On account of contact CH-Al in the circuits for windings IXR and 5XR, neither of these windings of the interlocking relay can again become energized until relay ,CH has again become energized after the train has cleared allth'ree of the track sections af-b, bc and c-d. 'I'herefore,'the flashing ofv the signal lamps will not be stopped while" a train is approaching the crossing from `either direction.

Although relay CH releases under the conditions referred to, it is, however, slow enough in releasing that it will not release during the normal transfer period from the main source of power to the auxiliary source while one of the track sections a-b, b-c and c-d is occupied.

The charging circuits for battery 2Q, including a back contact 4| of relay CRy in multiple with resistor 3|, provide onel or the other of two diierent charging rates for battery 2Q accord,-v ingas back contact 4| of relay CR is open or closed. Relay CR, whenever it becomes deenergized due to deenergi'zation of relay POB, or due to the deenergization of track relay 5TR as shown in Figs. 1, 3 and 5, or by other means shown in Figs. 1, 2 and 4, releases its armature which then closes its back contact 4|. This contact, by shunting around resistor 3|, permits a higher charging current to be suppliedfrom rectier 32 to battery 2Q. As already mentioned, relay CR, after becoming deenergized, will not open its back contact 4| when one of its control circuits isV again closed, until battery 2Q is fully charged.

4The characteristics of relay CR are also such that it will not release and close its back contact 4| upon a decrease in the voltage in battery 2Q -while a control circuit for relay CR is closed,

until the battery is completely discharged. Unless some means were provided for at times opening the control circuit for relay CR, other than the failure of the main source of power causing power-off relay POB to become deenergized, battery 2Q might, therefore, become under-charged if the voltage of the main source of power were to remain low for a prolonged period of time, but if it were not low enough to cause relay POB to release front contact 40. All that is necessary for this purpose is to open the energizing circuit for relay CR long enough to cause its armature to drop. As soonas battery 2Q becomes fully charged aftercontact 4| of relay CR is closed, relay CR will again open this contact.

The desired result can be accomplished by means of a switch SW shown in the primary circuit for transformer TB in Fig. 1 and in the primary circuit for transformer TA in Fig. 2, which can be periodically opened manually by some authorized person such, for example, as a signal maintainer. Another means, for accomplishing this result automatically, is also shown in Fig. 1 as contact 5TRf-38, `by which relay CR becomes deenergized whenever a train enters section c-d. ContactY 39 of relay STRP protects against overcharge if the' train should remain in section c-d too long.

In the modicationof the apparatus shown in Fig. 2, contact CH-41 is omitted from the circuits for energizing interlocking relay XRf-SXR, but is included inthe circuit for slow releasing signal relay XRP, this circuit passing from terminal BB, through contact CII-41, iiagman contacts 66 and 61 of interlocking relay windings 5XR and Dm, respectively, and the winding of relay XRP to terminal CC. Flasher relay FL is here controlled by a back contact 68 of slow release signal relay XRP. f

Relay POAA is provided with a pick-up circuit passing from' the upper terminal of secondary winding [|6' ofxtransformer'TA, vthrough one or corresponding `portions of 'the winding of relay` POAA, 'and the front `point of contact 69 of relay POAA, tothe lower terminal of secondary wind ing IB of transformer TA. Relay POAA, upon becoming deenergized, can therefore not again become energized untilrelay XRPA is energized. It follows that if relay POAA should release its contacts due to low voltage while a train is approaching thecrossing, relayPOAA cannot `then alternately pick up and release its contacts 'and thus cause interruptions in the energization of the signal lights from `the auxiliary` source of power` while a train is approaching,

In Fig. 2, the operating circuits for the lights of `the. signals pass from the `lower terminal of secondary winding i6 of transformer TA, through the front point of contact 59 of relay POAA, `back pointof Contact 'rllof relay XRA?, contact elements 56 and 59 of relay FL inthe left-hand or righthand position, and the corresponding lampsfof thecrossing signals, and the front point of contact 'H of relay 4POAA to the upper terminal of secondary winding I6 of transformer TA. The lighting-circuits for the highway crossing signals arerhere` supplied with 4current `from battery 2Q through the back points of contacts 69 and 1I, when the main source of power fails.

In Fig. 2, the `charging control relay CR is normally `energized by a circuit passing from termi-` nali BB, through flagman contacts `IXR.-l2 and 5XR-l3, contact 4I] of relay POB, and the wind-` ing of relay CR to terminal CC.` When one or the other of the fiagman contacts -IXR'-11Z andi 5XR-13 becomes openeddue 'to the approach of a train, the circuit just. traced for relay CR will be opened'and, after a `brief period of time which is long enough for contact 4l of relay CR to close, a second circuit for relay CR will be closed, which is the same as the `circuit just traced except including contact XRP-M instead of the flagman contacts.

In Fig. 3, relay CR is controlled by` a circuit including contact'I'Re-Sa as in Fig. l, but relay STRP, and its Contact 39 included in multiple withcontact 5TR-38 .in Fig. l, are here omitted. A contact designated ETR-63 is. however, here included `in series with contact 4| of relay CR in the charging circuit for battery 2Q for preventing overcharging of battery 2Q inthe event of the prolonged occupancy of track section c-e-d.

In the arrangement shown in Fig. 4, relay CR is controlled by a circuit which includes contact Ml which is periodically opened, such for example as once every twenty-four hours, by some suitable means such, for example, as 'a synchro` nous motor M through a cam 33.

In the arrangement shown in Fig'. 5, relay CR;

the' front points and the closing of these contacts atl theirback points, or the opening of these contacts at their back points and the subsequent T closing at their front points, causes relay CR to. momentarily release its armature 'and close its back contact 4I. i i

l Although I havedescrbedthe: operation ci the apparatus shown in the accompanying drawings for only a few typical sets of conditions, it is` believed that the operation of thel apparatus can be readily traced, in viewof this description and is caused to momentarily release `its armature the accompanying drawings, for every other possibleset of conditions, including'westbound trafc movements. When an eastbound train occupies section cL-b, and when `a westbound train occupies section c-d, the highway crossing sig` nals will be operated to warniusersof the highway. that a train is approaching.` These signals continue to be operated when either an eastbound ora westbound'train occupies section b-c.

From the foregoing description and the accompanying drawings, it follows that in apparatus embodying my invention, I have provided `checking means which ensures that the operation `of a highway crossing signal will not be .falsely stopped, while va train is approaching a highway crossing; inevent of failure of a main source of power for energizing the track `circuits and the subsequent` arrival of a train followed by energization ofthe track circuitsby the main or an auxiliary source before the train reaches the crossing. The checking means could also be used i to protect against momentary interruptions of a single main source of power if the auxiliary source were omitted. I have also provided means for controlling the `charging rate for an auxiliary source of power comprising a storage battery, to` prevent undercharging and overcharging of the battery.

Although I have herein shown and described onlyr a few forms of apparatus embodying my in- Vention, it is understood that various changes and modifications may be made therein within the scope of the appended claimswithout departing lfrom the spirit `and scope of my invention.

Having thus described my invention, what I clairnzis:

1. In combination, a stretch of railway track intersected by a highway and including two seccuit for energizing said charging control relay by current from said storage battery, means controlled by said main source of power for opening said circuit for said charging control relay whenever said main source of power fails, a resistor, a

circuitincluding said resistor in multiple with a back contact of said charging control relay forl charging said storage battery from said main source of power, a checking stick relay, a pick-up circuit for said checking stick relay controlled by said track relays and a stick circuit for said checking stick relay controlled by a contact operatedi in response to current from said main source of power and both of said pick-up and stick circuits normally energized by current from said main source of power but energized from said storage battery if said main source fails and becoming deenergized if both said main and aux-Y iliary sources fail, highway signalv means adjacent said intersection,V directional means controlled by said track relays for normally eiecting energization of said highway signal means while a train is approaching said intersection but for discontinuing such energization while a train is receding from said intersection in one of said track sections or the other, and means controlled by y sive to a train on said stretch of track adjacent and in a i'lrst direction from said intersection, a second circuit responsive to a train on said stretch of track adjacentand in the opposite direction from said intersection, a main source of power for normally energizing said iirst and sec- -ond circuits, an auxiliary source of power comprising a storage battery for energizing said first and second circuits if saidV main source fails, a charging control relay, means for energizing said charging control relay by current'from said storage battery, means controlled by said main source of power for deenergizing said charging control relay if said main source of power fails, means controlled in part by a back contact of `said charging control relay for supplying charging current of greater magnitude to said storage battery when said back contact is closed than when said back contact is open, a checking relay, a pick-up circuit for said checking relay controlled by saidv first and second circuits and a stick circuit for said checking relay controlled by a contact which is responsive to current from said main source of` power for normally energizing said checking relay byvcurrent from said main source of power and for energizing said checking relay from said storage battery if said main source fails and said checking relay becoming deenergized if both said main and auxiliary sources fail, highway signal means adjacent said intersection, directional means controlled b-y said irst and second circuits for normally effecting energization of said highway signal means while a train is approaching adjacent said intersection but for discontinuing such energization while a train is receding from said intersection, and means controlled `by said Ichecking relay for effecting energization of said highway signal means if said checking relay is deenergized and if one of said sources of power is Asubsequently restored while either said first or said second cir' cuit is deenergized in response to a train.

3. In combination, a stretch of railway track intersected by a highway and including two sections the first of which extends in one direction from said intersection andthe second of which extends in the opposite direction from said intersection, a track circuit including a track relay for each of said sections, a main source of power `for normally energizing said track circuits, an

auxiliary source of power for .energizing said track circuits if said main source fails, a checking stick relay, a pick-up circuit for said check-V ing stick relay controlled by a front contact of each of said track relaysand a stick circuit for said checking stick relay controlled by a contact operated in response to current from said main f source of power and both of said pick-up and stickcircuits normally energized vby current from said main source of power'but energized from said auxiliary source if said 'main source fails and becoming deenergized if. both said main and auxiliary sources fail, vhighway signal means adjacent said intersection, directional means controlled by said track relays for normally effecting energization of said highway signal means While a train is approaching said intersection but for discontinuing such energization while a train is receding from said intersection in one of said track sections or the other, and means controlled by said checking relay for .effecting energization of said highway signal means if said checking relay is deenergized and one of said sources of power is subsequently restored while either of said sections is occupied by a train.

4. In combination, a stretch of railway track intersected by a highway, a first circuit responsive to a train on said stretch of track adjacent and in a iirst direction from said intersection, a second circuit responsive to a train on said stretch of track adjacent and in the opposite direction from said intersection, a main source of power for normally energizing said rst and second circuits, -an auxiliary source of power for energizing said first and second circuits if said main source fails, a checking relay, a pick-up circuit for said checking relay controlled by said rst and second circuits and a stick circuit for said checking relay controlledl by a contact which is responsive to current from said main source of power for normally energizing said checking relay by current from said main source of power and for energizing said checking relay from said auxiliary source if said main source fails and said checking relay becoming deenergized if both said main and auxiliary sources fail, highway 1 signal means adjacent said intersection, direcy sources of power is subsequently restored while either said rst or said second circuit is deen.

ergized in response to a train.

5. In combination, a stretch intersected by a highway,

of railway track a rst circuit responsive to a train on said stretch of track adjacent and in a iirst direction from said intersection, a second circuit responsive to a train on said stretch of track adjacent and in the opposite direction from said intersection, a main source of power for normally energizing said rstA and second circuits, a checking relay, a pick-up circuit for said checking relay controlled by said rst and second circuits for energizing said checking relay by current from said main source of power, means controlled by a contact operated in response to current from said main source of power for retaining said checking relay energized by current from said main source of power when a train approaches said intersection and said checking relay becoming deenergized if said main source of power fails, highway signal means adjacent said intersectiomdirectional means controlled by said first and' second circuits for normally effecting energization of said highway signal means while a train is approaching adjacent said intersection but for discontinuing such energization while a train is receding from said intersection and means controlled by said checking relay for effecting energization of said highway signal means if said checking relay is deenergized and if said main source of power is subsequently restored while either said first or said second circuit is deenergized in `response to a train.

6. In combination, a stretch of railway track intersected by a highway, a first circuit responsive to a train on said stretch of track adjacent and in a rst direction from said intersection, a second circuit responsive to a train on said stretch of` track adjacent and in the opposite direction from said intersection, a main source of power for .energizing said rst and second circuits, a checking stick relay, a pick-up circuit for said checking stick relay closed by said first and second circuits when there is no train on said stretch of track adjacent said intersection and a stick circuit for said checking stick relay controlled by a contact operated in response te current from said main source of power and both of said pick-up and stick circuits energized by current from said main source of power and becoming deenergized if said main source of power fails, highway signal means for said intersection, directional means controlled by said rst and second circuits for normally effecting energization of said highway signal means while a train is approaching said intersection but for discontinuing such energization while a train isireceding `from said intersection, and means controlled bysaid checking relay for effecting energization of said highway signal means if said main source of power fails and if said main source of power is subsequently restored while either said rst or said second circuit is deenergized in response t0 a train.

7. In combination, a stretch of railway track intersected by a highway, a first circuit responsive to a train on said stretch of track adjacent and in a rst direction from said intersection, a second circuit responsive to a train on `said stretch of track adjacent and in the opposite direction from said intersection, a main source of power normally .energizing said first and second circuits, an auxiliary source of power cornprising a storage battery for energizing said first and second circuits if said main source fails, a charging control relay, an interlocking relay one winding of which is controlled by said rst circuit and the other winding of which is controlled by said second circuit and each of said windings controlling agman contacts, a slow release relay, a circuit controlled by a agman contact of each of said interlocking relay windings in se-` ries with each other for energizing said slow release relay, a control circuit `for said charging control relay including a flagrnan contact of each of said interlocking relay windings in series with each other and in multiple with a back contact of said slow release relay, and means controlled by said charging control relay for charging said storage battery.

CHARLES W. FAILOR. 

